The base, which has a brown colour, is filtered and dissolved
in hot spirit, with the addition of a few drops of concentrated «
ammonia. Yield, about 8 grams.
C0H6N:N.NHC0H6 + H.C0H4NH2.HC1 -
C0H5N:N.C0H4.NH2 + CCH5NH2.HC1. I
Properties.—Orange prisms ; m. p. 127°. , J
Reaction.—Make a solution of 4 grams stannous chloride in
10 c.c. cone, hydrochloric acid, add 2 grams aminoazobenzene, J»'
and boil for a few minutes. On cooling crystals of the hydro- /
chlorides of aniline and ^-phenylenediamine separate out. 1
The liquid is filtered and washed with a little cone, hydro- ;" j,
chloric acid to remove the tin salts. If the precipitate is ' \>
dissolved in water and made alkaline with caustic soda, a '*
mixture of liquid aniline and solid/-phenylenediamine is pre- \
cipitated, from which the former may be removed by filtering,
washing, and draining on a porous plate. ^;
C0HBN:N.C0H4NHo + "2SnCl2 + 4HC1= />
C0H5NH2 4- H2N.CGH4.NH2 + 2SnCl4. '*
/-Phenylenediamine, when warmed with dilute sulphuric acid ''
and potassium bichromate or lead peroxide, gives the odour of ji
quinone (p.-192). After warming and cooling, extract with ether. flL
The ethereal solution has a yellow colour. Decant the ether 1p
extract on to a watch-glass and leave it to evaporate in the air. 'ft
A deposit of microscopic yellow crystals remains. See Appen- * ,,
diX) p. 286. ||*
PREPARATION 71. ^
Phenylhydrazine, C0H5NH,NH2 -,f
E. Fischer, Annalen, 1878, 190, .167 ; Meyer, Lecco, Ber^ \\. '
1883, 16, 2976 ; Meyer and Jacobson, Lchrlntch, 2, 305. ^
20 grms. aniline. !\ ^
200 „ (170 c.c.) cone, hydrochloric acid. ' *
20 „ sodium nitrite (in 100 c.c. water). ^
120 „ crystallised stannous chloride (in 100 c.c. ^
cone, hydrochloric acid). . ?;'
The aniline is dissolved in the concentrated hydrochloric k\(
acid and cooled to o° in a freezing mixture. The solution of ' i (.